Eating or drinking cyanide-containing foods may cause health effects. Breathing cyanide gas, especially in a poorly ventilated space, has the greatest potential for harm. Lethal exposures to cyanides result only from accidents or intentional acts.
Because of their quick-acting nature, cyanides may be used as agents of terrorism. After exposure, cyanide quickly enters the bloodstream. The body handles small amounts of cyanide differently than large amounts. In small doses, cyanide in the body can be changed into thiocyanate, which is less harmful and is excreted in urine.
In the body, cyanide in small amounts can also combine with another chemical to form vitamin B 12 , which helps maintain healthy nerve and red blood cells.
Large doses of cyanide prevent cells from using oxygen and eventually these cells die. The heart, respiratory system and central nervous system are most susceptible to cyanide poisoning. The health effects from high levels of cyanide exposure can begin in seconds to minutes. Some signs and symptoms of such exposures are:.
The severity of health effects depends upon the route and duration of exposure, the dose, and the form of cyanide. Moving away from the point of exposure to fresh air is an important first step in treating cyanide exposure.
Cyanide poisoning can be further treated by medical professionals. Often patients are given oxygen. Two antidotes sodium nitrite and sodium thiosulfate are usually used to stop the effects of serious cyanide poisoning. Other drugs may be necessary to control additional health effects of cyanide such as seizures. People who experience serious signs and symptoms will need immediate hospital care, especially individuals who have "passed out" or are unconscious.
Any delay could result in death. While an elevated blood cyanide concentration may indicate that someone has been exposed to cyanide, laboratory testing for cyanide exposure will not be useful in making emergency treatment decisions. A patient exposed to cyanide should not expect medical personnel to do these tests before treatment. Treatment should not be delayed if signs and symptoms are present and exposure is believed to have occurred.
Agency for Toxic Substances and Disease Registry. Toxicological Profile for Cyanide. Division of Toxicology, U. Department of Health and Human Services.
Medical Management Guidelines for Hydrogen Cyanide. Two notorious incidents in recent history-the Jonestown Massacre in and the Tylenol poisonings in highlight the lethality of this poison. First isolated in , cyanide is a compound composed of carbon triple bonded to nitrogen CN. Cyanide can be released from natural sources, including some foods, and it is contained in several industrial chemicals and in cigarette smoke.
It is also used in manufacturing and in pesticides. In medicine, cyanide can be found in the widely used anti-hypertensive, sodium nitroprusside, each molecule of which contains 5 molecules of cyanide. The most common cause of cyanide poisoning is smoke inhalation in fires. The use of cyanide in warfare dates to the Franco-Prussian War , during which Napoleon III urged his troops to dip their bayonet tips in the poison.
Roman Emperor Nero also used cyanide-containing cherry laurel water as a poison. This poisonous compound poses an ongoing threat as a weapon of terrorism, whether it is delivered in oral form via sodium cyanide and potassium cyanide or as a gas via hydrogen cyanide and cyanogen chloride. Cyanide poisons the mitochondrial electron transport chain within cells and renders the body unable to derive energy adenosine triphosphate-ATP from oxygen.
Specifically, it binds to the a3 portion complex IV of cytochrome oxidase and prevents cells from using oxygen, causing rapid death. When ingested as sodium or potassium cyanide, the lethal dose is mg. Cyanide kills quickly: death occurs within seconds of a lethal dose of cyanide gas and within minutes of ingestion of a lethal dose of cyanide salt. The central nervous system CNS and cardiovascular systems are chiefly affected.
Signs and symptoms of cyanide poisoning include the following:. Cardiovascular : decreased inotropy, bradycardia followed by reflex tachycardia, hypotension, and pulmonary edema; and. Survivors may suffer Parkinson's disease, ataxia, optic atrophy, and other neurological disorders.
Cyanide intoxication is largely a clinical diagnosis; however, several laboratory features are suggestive:. Cyanide blood levels are confirmatory, as results are not obtainable in time for initial diagnosis.
This procedure produces impure solution of cyanide which often can be used to poison as is, or purified by a very simple process to produce almost pure sodium cyanide.
Some of the materials which are widely available and which can be readily decomposed by heat, pyrolysed, to produce hydrocyanic acid are:. Larger yields of cyanide are obtained if fresh air is not available to contact the heated material during the pyrolysis. Passing a small stream of nitrogen or helium over the heated material and then into the basic solution increases the yield of hydrocyanic acid.
Although the yield of cyanides in these processes is not large, enough cyanide can be recovered to poison a person since the quantity needed is very small. Some victims who die due to smoke inhalation and fire actually die from breathing excess HCN. Most states do not allow using polyurethane mattresses, in particular in prisons, because the gases emitted upon their combustion in limited air were the cause of death of some inmates.
The main symptoms of acute poisoning by cyanides are due to the interference of cyanide in the assimilation and distribution of oxygen in the body. Whether the cyanide source is HCN or ingestion of food containing a water soluble cyanide such as potassium or sodium salt, the poisoning mechanism is the same. The cyanide ions react irreversibly with the iron, in particular with the iron in the cytochrome c oxidase and hemoglobin.
Since cyanides interfere with the absorption of oxygen and thus with the production of energy in the body, an increased exposure to cyanide will gradually show as headache, nausea, confusion, weakness, fatigue, loss of coordination, hyperventilation, cardiac arrhythmia, bradycardia, loss of consciousness and coma. Death typically occurs due to problems with the nervous system or the heart.
Post mortem analysis of blood of poisoned people shows that concentrations of about 3 micrograms cyanide per ml were sufficient to kill the person. Incorporation of cyanide, mainly HCN, via the breathing, is a lot more rapid than via ingestion. A person will die instantly if the HCN concentration is above ppm, Parts per million , and after 10 and 30 minutes respectively if the HCN concentrations are respectively and ppm. Since cyanides effect the function of muscles and produce confusion, many victims die because they lose their coordination and ability to escape to areas with clean air.
This happens sometimes when people are trapped in a burning house and the air contains cyanide. If it is suspected that a victim was poisoned by ingesting cyanide, it imperative that it will be determined QUICKLY since the poisoning effect of cyanide is very quick. To this end, Appealing products Inc. These detectors allow emergency personnel to react timely and save the victim. The KT kit detects cyanides and up to 30 other poisons.
The STPD detects the same poisons but has a much shorter shelve life. The CAK kit detects only cyanides, azides, sulfides and chromates. ChemSee now also offers home-users the ability to test their foods directly for Cyanide using the CN Detector. More information on the CN Detector can be found below:. I am text block. Click edit button to change this text. Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.
Cyanides may be detected using conventional laboratory techniques and instruments. Unfortunately, these techniques require expensive and sophisticated instrumentation and highly trained personnel and the results are NOT obtained immediately. Since in real emergency situations such amenities may not be available, and a timely response is critical to save a person live, the value of the laboratory services is mainly in post mortem investigations.
Since the poisoning mechanism of cyanides is based on the reaction of the free cyanide ion with metals, mainly iron and thus preventing the proper absorption and assimilation of oxygen, antidotes to cyanide poisoning utilize injecting relatively large amounts of metallic ions which rapidly and irreversibly react with the cyanide ion.
This process depletes the concentration of the cyanide ions in the blood and thus reduces the amount of cyanide available for reaction with the iron and deactivating it. The most important qualities of a good antidote for cyanide poisoning are:. One of the antidotes used today is hydroxocobalamin, a naturally available form of vitamin B This compound reacts with cyanide to form cyanocobalamin, which is eliminated safely by the kidneys. The cyanide reacts with the cobalt in the hydroxocobalamin and thus consumed and becomes unavailable to react with the iron.
An antidote kit based on this chemistry is sold under the brand name Cyanokit and was approved by the FDA in The most important mechanism which eliminates cyanide from the body involves the enzymatic conversion of the cyanide to the relatively non-toxic thiocyanate ion. CNS
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